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In the present work, we investigated the minimal inhibitory concentration (MIC) against fungal strains (Fonsecaea pedrosoi, Microsporum canis, Candida albicans, Cryptococcus neoformans), and cytotoxicity to normal cell lines for modified red angico gum (AG) with eterifying agent N-chloride (3-chloro-2-hydroxypropyl) trimethylammonium (CHPTAC). Quaternized ammonium groups were linked to AG backbone using N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride. The chemical features of the quaternized gum derivatives (QAG) were analyzed by: FTIR, elemental analysis, Zeta potential and gel permeation chromatography. The angico quaternizated gum presented a degree of substitution (DS) of 0.22 and Zeta potential of +36.43. For the antifungal test, it was observed that unmodified gum did not inhibit fungal growth. While, QAG inhibited the growth of most fungi used in this study. By AFM technique QAG interacted with the fungal surface, altering wall roughness significantly. The probable affinity of fragments of the QAG structure for the fungal enzyme 5I33 (Adenylosuccinate synthetase) has been shown by molecular docking. Low cytotoxicity was observed for polymers (unmodified gum and QAG). The results demonstrate that the quaternized polymer of AG presented in this study is a quite promising biomaterial for biotechnological applications.

This study presents a new polymeric and multielectronic system, the poly-Alizarin Red S (PARS), obtained from the electropolymerization of Alizarin Red S (ARS) dye on an edge-plane pyrolytic graphite electrode (EPPGE) surface. During EPPGE/PARS electrochemical characterization, we identified seven stable and reversible redox peaks in acidic medium (0.10 mol L−1, pH 1.62 KH2PO4), which indicated its mechanisms underlying electropolymerization and electrochemical behavior. To the best of our knowledge, this is the first study to use an EPPGE/PARS electrode to detect oxandrolone (OXA) in artificial urine, where PARS acts as a synthetic receptor for OXA. The interactions of OXA with EPPGE/PARS as well as the properties of PARS were investigated using density functional theory (DFT). Atomic force microscopy (AFM) was used to characterize EPPGE/PARS, and it was found that the PARS polymer formed a semi-globular phase on the EPPGE surface. The limit of detection for OXA found by the sensor was close to 0.50 nmol L−1, with a recovery rate of approximately 100% in artificial urine. In addition to the application proposed in this study, EPPGE/PARS is a low-cost product that could be applied in several devices and processes, such as supercapacitors and electrocatalysis.

COVID-2019 disease, caused by the 2019-nCOV virus or SARS-Cov-2, adds up to just over 290 thousand cases and 12 thousand deaths worldwide. No clinical studies are indicating effective treatments, and the identification of suitable antiviral agents is a crucial step in combating the pandemic. This research constitutes a survey of SARS-Cov-2 proteins from the Protein Data Bank (PDB), eligible as targets for docking of inhibitory substances. later, in silico tests were performed with two enzymatic targets in interaction with the drugs Ledipasvir and Ombitasvir. Prospecting in the PDB reported 29 proteins. 6vsb and 6m17 were selected for docking with Ledispasvir, resulting in interaction energies equal to -6.88 and -6.25kJ / mol, respectively. For the same targets, the drug Ombitasvir obtained -5.96 and -4.53kJ / mol. The study showed the advances in COVID-19 research, presenting 29 structures. The drugs tested showed favorable parameters for continuing in vitro and clinical studies. O vírus COVID-2019, 2019-nCOV ou SARS-Cov-2 soma pouco mais de 290 mil casos e 12 mil mortes pelo mundo. Não existem estudos clínicos indicando tratamentos eficazes, e a identificação de agentes antivirais adequados constitui-se um passo crucial no combate à pandemia. O presente trabalho constitui o levantamento de proteínas do SARS-Cov-2 a partir do Protein Data Bank (PDB), elegíveis como alvos para docagem de substâncias inibitórias. Posteriormente, foram realizados testes in sílico, com dois alvos enzimáticos em interação com os fármacos Ledipasvir e Ombitasvir. A prospecção no PDB reportou 29 proteínas. Selecionou-se 6vsb e 6m17 para docagem com Ledispasvir, resultando energias de interação iguais a -6.88 e -6.25kJ/mol, respectivamente. Para os mesmos alvos, o fármaco Ombitasvir obteve -5,96 e -4,53kJ/mol. O estudo evidenciou o avanço nas pesquisas relacionadas ao COVID-19, apresentando 29 estruturas enzimáticas. Os fármacos Ledipasvir e Ombitasvir apresentaram parâmetros favoráveis para a continuação de estudos in vitro e clínicos.

Objetivo: Avaliar a atividade bioativa da desloratadina através de estudos in sílico por docagem molecular em organismos do gênero Schistosoma. Metodologia: Para o estudo foram coletadas proteínas em 3D dos alvos cathepsin B1 (2cb1), purine nucleoside phosphorylase (pnp), thioredoxin glutathione reductase (tgr), e uridine phosphorylase (up) no banco de dados Protein Data Bank (PDB). As análises de docagem foram realizadas pelo software Autodock Tools (ADT) versão ADT 1.5.6. Posteriormente o ligante desloratadina foi obtido no banco de dados PubChem em estrutura 2D e desenhado no programa GaussView 5.0 e otimizado pelo software Gaussian 09W em método Hartree-Fock na base Default Spin/3-21G. O restante dos parâmetros foi definido de acordo com o método padrão. Resultados: De todos os alvos analisados, a desloratadina obteve os melhores resultados nos receptores up e 2cb1 com energias de ligação de -8,49 e -8,35 Kcal.mol-1 respectivamente. Conclusão: Esses valores demonstram uma boa afinidade molecular em interação dos organismos com a droga desloratadina, além de terem resultados elevados de constante de inibição, demonstrando atividade bioativa da droga antiesquistossomose. Com os presentes resultados in sílico, a droga se torna uma alternativa em estudos bioativos antiesquistossomose, podendo dar continuidade em ensaios in vitro e ex vivo.